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            <h2 class="title" style="clear: both"><a id="bulk"></a>Bulk Transfers</h2>
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      <p>
                    By default, messages are sent from the master to replicas as they are generated.
                    This can degrade replication performance because the various participating
                    environments must handle a fair amount of network I/O activity.
            </p>
      <p>
                    You can alleviate this problem by configuring your master environment for bulk
                    transfers. Bulk transfers simply cause replication messages to accumulate in a
                    buffer until a triggering event occurs. When this event occurs, the entire
                    contents of the buffer is sent to the replica, thereby eliminating excessive
                    network I/O.
            </p>
      <p>
                    Note that if you are using replica to replica transfers, then you might want any
                    replica that can service replication requests to also be configured for bulk
                    transfers.
            </p>
      <p>
                    The events that result in a bulk transfer of replication messages to a replica
                    will differ depending on if the transmitting environment is a master or a
                    replica.
            </p>
      <p>
                    If the servicing environment is a master environment, then bulk transfer
                    occurs when:
            </p>
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            <p>
                                    Bulk transfers are configured for the master environment, and
                            </p>
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            <p>
                                    the message buffer is full or
                            </p>
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                                    a permanent record (for example, a transaction commit or a
                                    checkpoint record) is placed in the buffer for the replica.
                            </p>
          </li>
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      <p>
                    If the servicing environment is a replica environment (that is, replica to replica
                    transfers are in use), then a bulk transfer occurs when:
            </p>
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            <p>
                                    Bulk transfers are configured for the transmitting replica, and
                            </p>
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          <li>
            <p>
                                 the message buffer is full or
                            </p>
          </li>
          <li>
            <p>
                                    the replica servicing the request is able to completely satisfy
                                    the request with the contents of the message buffer. 
                            </p>
          </li>
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      <p>
                    To configure bulk transfers, specify

                    <span>
                        <code class="literal">DB_REP_CONF_BULK</code> to
                            <code class="methodname">DB_ENV-&gt;rep_set_config()</code>
                            
                        and then specify <code class="literal">1</code> to the <code class="literal">onoff</code>
                        parameter. (Specify <code class="literal">0</code> to turn the feature off.)
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